Frequency modulation filter

Abstract

The invention discloses a frequency modulation filter, which comprises a cavity, a limiting plate, a resonance rod and a driving device, the limiting plate is buckled above the cavity, the driving device is connected with each frequency modulation gear, so that synchronous frequency modulation of each resonant cavity of the filter can be realized, and when the resonant frequency of a certain resonant cavity in the filter needs to be independently adjusted, the resonant frequency of the resonant cavity can be independently adjusted. The threaded limiting piece of the frequency modulation mechanism corresponding to the resonant cavity is unscrewed, so that the first elastic piece overcomes the gravity of the tuning gear and the elastic force of the second elastic piece, the tuning gear is separated from the driving device, the resonant frequency of the resonant cavity can be independently adjusted, and after adjustment is completed, the threaded limiting piece is screwed tightly. Therefore, synchronous frequency modulation of all the resonant cavities of the filter can be realized, independent frequency modulation of a single resonant cavity can also be realized, and accurate frequency modulation of the filter is realized while frequency modulation of the filter is facilitated.

Description

Technical Field

[0001] The present invention relates to the technical field of filters, and in particular to a frequency modulation filter. Background Art

[0002] In the field of communications, it is widely used as a frequency selection device. It can filter various power supplies, signals, etc. to ensure the stability and reliability of circuit operation. It is a very important component in the field of electronic communications.

[0003] The tuning of the filter is mainly carried out through a frequency modulation screw. To facilitate the operation of the frequency modulation screw, the patent document with publication number CN113437459A discloses a filter that realizes frequency modulation by a worm gear transmission structure. The filter is provided with a tuning mechanism and a driving mechanism. The tuning mechanism is through a tuning rod, a worm gear and a worm. Each tuning rod is meshed with the worm gear through the worm gear. The driving mechanism is connected to the worm. By driving the worm, the tuning rods can be driven to rotate synchronously, thereby realizing the synchronous adjustment of the resonant frequency of each resonant cavity of the filter.

[0004] Although the existing filter can facilitate the frequency modulation of the filter through the setting of the worm gear, the tuning rod is always in a meshing state with the worm through the worm gear, so the tuning rod cannot be adjusted separately, making it difficult to achieve accurate frequency modulation of the filter. Summary of the invention

[0005] The purpose of the present invention is to overcome the above technical deficiencies and propose a frequency modulation filter to solve the technical problem that the worm gear frequency modulation filter in the prior art is difficult to achieve accurate frequency modulation of the filter.

[0006] In order to achieve the above technical objectives, the present invention adopts the following technical solutions: In the first aspect, the present invention provides a frequency modulation filter, which includes a cavity body provided with a resonant cavity, a limit plate engaged on the top of the cavity, a resonant rod installed in the resonant cavity, and a driving device for driving the resonant rod to move, the resonant rod is provided with a step, the resonant rod is sleeved with a limit sleeve, a tuning gear meshing with the driving device is installed between the limit sleeve and the step, a first elastic member that can drive the tuning gear to disengage from the driving device is provided between the tuning gear and the step, a second elastic member is also sleeved outside the limit sleeve, one end of the second elastic member abuts against the limit plate, and the other end abuts against the tuning gear, which can drive the tuning gear to engage with the driving device, and a threaded limit member that limits the limit sleeve on the resonant rod is also installed at the top of the resonant rod.

[0007] In some embodiments, the first elastic member and the second elastic member are springs.

[0008] In some embodiments, the elastic coefficient of the first elastic member is greater than the elastic coefficient of the second elastic member.

[0009] In some embodiments, the resonance rod is provided with a rotation limiting plane, and the rotation limiting plane is used to limit the rotation of the tuning gear relative to the resonance rod.

[0010] In some embodiments, the step is provided with a first limiting groove, and the lower end of the first elastic member is mounted in the first limiting groove.

[0011] In some embodiments, the tuning gear is provided with a second limiting groove, and the upper end of the first elastic member is mounted in the second limiting groove.

[0012] In some embodiments, the tuning gear is a worm gear, the driving device includes a motor, a worm and a transmission gear, the worm is meshed with the tuning gear, the motor is installed in the cavity, and the transmission gear is connected to the worm and the shaft of the motor.

[0013] In some embodiments, the threaded limiting member includes a screw, and the screw is threadedly connected to the resonance rod to limit the limiting sleeve.

[0014] In some embodiments, the threaded limiter includes a nut, a threaded connector is disposed on the top of the resonance rod, and the nut is threadedly connected to the threaded connector to limit the limit sleeve.

[0015] Compared with the prior art, the frequency modulation filter provided by the present invention is provided with a cavity, a limit plate, a resonance rod and a driving device. The limit plate is buckled on the top of the cavity, and the resonance rod and the driving device are installed in the resonance cavity. When the resonance rod moves, the length of the resonance rod extending into the tuning cavity can be adjusted to realize the frequency modulation of the filter. The driving device can drive the tuning gear and the resonance rod to rotate by driving the tuning gear to realize the automatic frequency modulation of the filter. The connection between the driving device and each frequency modulation gear can realize the synchronous frequency modulation of each resonance cavity of the filter, which provides convenience for the frequency modulation of the filter. It is only necessary to adjust the resonance frequency of a resonance cavity in the filter. When adjusting individually, the threaded limiter of the frequency modulation mechanism corresponding to the resonant cavity is loosened, so that the first elastic member can overcome the gravity of the tuning gear and the elastic force of the second elastic member, drive the tuning gear to slide, and disengage the tuning gear from the driving device. At this time, the resonant frequency of the resonant cavity can be adjusted individually by controlling the tuning rotation individually. After the adjustment is completed, the threaded limiter is tightened to make the tuning gear mesh with the driving device again. Therefore, while realizing synchronous frequency modulation of each resonant cavity of the filter, independent frequency modulation of a single resonant cavity can also be realized, thereby facilitating the frequency modulation of the filter and realizing accurate frequency modulation of the filter. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1is a schematic diagram of the structure of a frequency modulation filter provided by an embodiment of the present invention; Figure 2 is an exploded view of a hidden cavity of a frequency modulation filter provided by an embodiment of the present invention; Figure 3 It is a cross section of the tuning gear provided by the embodiment of the present invention in a state of being connected to a worm gear and in a state of being separated from the worm gear; Figure 4 It is a structural schematic diagram of a hidden cavity and a driving device of a frequency modulation filter provided by an embodiment of the present invention; Figure 5 is a front view of a resonance rod of a frequency modulation filter provided by an embodiment of the present invention; Figure 6 is along Figure 5 Sectional view along line AA; Figure 7 It is a schematic diagram of the structure of a resonant rod and a tuning gear provided by an embodiment of the present invention; Reference numerals in the figures: 10—resonance rod 11—rotation limit plane 12—step 13-limit sleeve 14-threaded connector 20-tuning gear 21—second limiting groove 30—thread limiting member 31—nut 32 - locking screw 40 - limit plate 50 - second elastic member 60—first elastic member 70—cavity 71—resonant cavity 80—driving device 81—motor 82—worm 83—transmission gear 121—first limiting groove. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0018] In order to solve the technical problem that it is difficult to achieve precise frequency modulation of the worm gear frequency modulation filter in the prior art, an embodiment of the present invention provides a frequency modulation filter. The frequency modulation filter can drive each frequency modulation gear by setting a driving device, synchronously modulate the frequency of each resonant cavity of the filter, and simultaneously achieve precise frequency modulation of the filter by separately modulating the frequency of a single resonant cavity.

[0019] like Figure 1-7As shown, the frequency modulation filter provided by the embodiment of the present invention includes a cavity 70 provided with a resonance cavity 71, a limit plate 40 buckled on the top of the cavity 70, a resonance rod 10 installed in the resonance cavity 71, and a driving device 80 for driving the resonance rod 10 to move, the resonance rod 10 is provided with a step 12, the resonance rod 10 is sleeved with a limit sleeve 13, a tuning gear 20 meshing with the driving device 80 is installed between the limit sleeve 13 and the step 12, a first elastic member 60 that can drive the tuning gear 20 to disengage from the driving device 80 is provided between the tuning gear 20 and the step 12, a second elastic member 50 is also sleeved outside the limit sleeve 13, one end of the second elastic member 50 abuts against the limit plate 40, and the other end abuts against the tuning gear 20, which can drive the tuning gear 20 to engage with the driving device 80, and a threaded limit member 30 that limits the limit sleeve 13 on the resonance rod 10 is also installed at the top of the resonance rod 10.

[0020] In this embodiment, the tuning gear 20 must be able to slide along the axial direction of the resonance rod 10 and also drive the resonance rod 10 to rotate under the drive of the driving device 80 .

[0021] It can be understood that the resonance rod 10 can be provided with an axially extending groove or convex rib structure, and the inner side of the tuning gear 20 can be engaged with the groove or convex rib structure of the resonance rod 10, so that it can slide axially along the resonance rod 10 and drive the resonance rod 10 to rotate under the drive of the driving device 80.

[0022] In one embodiment, Figure 7 As shown, the resonance rod 10 is provided with a rotation limiting plane 11, and the rotation limiting plane 11 is used to limit the rotation of the tuning gear 20 relative to the resonance rod 10. Specifically, the tuning gear 20 is sleeved on the resonance rod 10, and the rotation of the tuning gear 20 is limited by the rotation limiting plane 11, so that the tuning gear 20 can rotate under the drive of the tuning gear 20. Therefore, through the setting of the rotation limiting plane 11, while the tuning gear 20 slides along the sliding axis of the resonance rod 10, the resonance rod 10 can also be driven to rotate under the drive of the driving device 80.

[0023] It can be understood that the driving device 80 can be a driver and several gears, each gear meshes with each other and meshes with the tuning gears 20 of each frequency modulation mechanism respectively. The driver can drive all the gears and the tuning gear 20 to rotate by driving the rotation of one of the gears, so as to realize the synchronous frequency modulation of each resonant cavity 71, and the tuning gear 20 can be separated from the corresponding meshing gear by sliding; the driving device 80 can also be a driver and a rack, the rack meshes with the tuning gear 20 of each frequency modulation mechanism, and the driver can drive the tuning gears 20 to rotate synchronously by driving the rack to move, so as to realize the synchronous frequency modulation of each resonant cavity 71, and the tuning gear 20 can be separated from the rack by sliding; the driving device 80 can also be a driver and a belt, the belt is sleeved on the tuning gear 20 of each frequency modulation mechanism, and the driver can drive the tuning gears 20 to rotate synchronously by driving the belt to rotate, so as to realize the synchronous frequency modulation of each resonant cavity 71, and the tuning gear 20 can be separated from the belt by sliding.

[0024] In one embodiment, Figure 2 As shown, the tuning gear 20 is a worm gear, and the driving device 80 includes a motor 81, a worm 82 and a transmission gear 83. The worm 82 is rotatably connected to the bracket between the limit plate 40 and the cover plate 72 and meshes with the tuning gear 20 of each frequency modulation mechanism. The motor 81 is installed on the cover plate 72, and the transmission gear 83 is connected to the worm 82 and the shaft of the motor 81. The driving force of the motor 81 can be transmitted to the worm 82, driving the worm 82 to rotate, and finally driving the tuning gears 20 to rotate synchronously, thereby realizing the synchronous frequency modulation of each resonant cavity 71. The tuning gear 20 can be separated from the worm 82 by sliding.

[0025] In this embodiment, the step 12 can provide support for the first elastic member 60 , so that the first elastic member 60 generates a driving force to drive the tuning gear 20 to slide.

[0026] In this embodiment, Figure 2 and 6 As shown, the step 12 is provided with a first limiting groove 121, and the lower end of the first elastic member 60 is mounted in the first limiting groove 121. Specifically, the first limiting groove 121 can provide stability for the lower end of the first elastic member 60.

[0027] In this embodiment, Figure 2 and 6 As shown in FIG. 7 , the tuning gear 20 is provided with a second limiting groove 21, and the upper end of the first elastic member 60 is mounted in the second limiting groove 21. Specifically, the second limiting groove 21 can provide stability for the upper end of the first elastic member 60.

[0028] In this embodiment, Figure 3-6As shown, the limit sleeve 13 is slidably connected to the resonance rod 10, the lower end of the limit sleeve 13 is against the tuning gear 20, and the upper end of the limit sleeve 13 is penetrated by a limit plate 40, which can be used for radial limiting, thereby avoiding radial deflection of the frequency modulation mechanism and ensuring the radial stability of the frequency modulation mechanism. The second elastic member 50 can provide limiting for the tuning gear 20 together with the limit sleeve 13 through the elastic force acting on the tuning gear 20, thereby avoiding excessive force between the limit sleeve 13 and the tuning gear 20, which causes wear to the tuning gear 20 and the limit sleeve 13.

[0029] It can be understood that the first elastic member 60 and the second elastic member 50 can be structures such as rubber members, compression springs or springs, and only need to be able to provide a driving force for the tuning gear 20 to slide along the resonance rod 10; In this embodiment, Figure 3-6 As shown, the first elastic member 60 and the second elastic member 50 are both springs.

[0030] In this embodiment, the elastic coefficient of the first elastic member 60 is greater than the elastic coefficient of the second elastic member 50. Specifically, when the locking screw 32 is released from locking the limiting sleeve 13, the first elastic member 60 overcomes the gravity of the tuning gear 20 and the elastic force of the second elastic member 50, drives the tuning gear 20 to slide, and finally separates the tuning gear 20 from the driving device 80. After the tuning gear 20 is separated from the driving device 80, the limiting module 30 is released from limiting the tuning gear 20. At this time, the first elastic member 60 and the second elastic member 50 can provide force for the tuning gear 20 on the upper and lower sides of the tuning gear 20, so that the tuning gear 20 is in a certain balanced state, thereby ensuring the stability of the tuning gear 20, and further facilitating the individual frequency modulation of the frequency modulation structure.

[0031] In this embodiment, Figure 3 As shown, the threaded stopper 30 includes a nut 31, and a threaded connector 14 is provided at the top of the resonance rod 10. The nut 31 is threadedly connected to the threaded connector 14 to limit the stop sleeve 13. Specifically, the nut 31 can be threadedly connected to the threaded connector 14 to lock the stop sleeve 13, thereby limiting the tuning gear 20. When the tuning gear 20 is separated from the driving device 80, it is only necessary to loosen the nut 31.

[0032] In one embodiment, Figure 1-2 As shown in Figures 4-6, the threaded stopper 30 includes a locking screw 32, which is threadedly connected to the resonance rod 10 to lock the stopper sleeve 13. Specifically, the locking screw 32 can lock the stopper sleeve 13, and when the tuning gear 20 needs to be separated from the driving device 80, it is only necessary to loosen the locking screw 32.

[0033] In order to better understand the present invention, the following Figures 1 to 7The technical solution of the present invention is described in detail: when the frequency modulation filter is performing frequency modulation, the motor 81 drives the turbine to rotate through the transmission gear 83. The turbine rotates to drive the tuning gears 20 meshing with it to rotate, and then drives the tuning gears 20 to rotate synchronously to achieve synchronous frequency modulation of each resonant cavity 71. When the resonant frequency of a certain resonant cavity 71 in the filter needs to be adjusted individually, the threaded limiter 30 of the frequency modulation mechanism corresponding to the resonant cavity 71 is loosened, so that the first elastic member 60 overcomes the gravity of the tuning gear 20 and the elastic force of the second elastic member 50, and drives the tuning gear 20 to slide, so that the tuning gear 20 is disconnected from the turbine. At this time, the resonant frequency of the resonant cavity 71 can be adjusted individually by controlling the tuning rotation individually. After the adjustment is completed, the threaded limiter 30 is tightened to make the tuning gear 20 mesh with the turbine again.

[0034] The specific implementation of the present invention described above does not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A frequency modulation filter, comprising a cavity body provided with a resonant cavity, a limit plate buckled on the upper part of the cavity, a resonant rod installed in the resonant cavity, and a driving device for driving the resonant rod to move, characterized in that: The resonance rod is provided with a step, and a limit sleeve is sleeved on the resonance rod. A tuning gear meshing with the driving device is installed between the limit sleeve and the step. A first elastic member that can drive the tuning gear to disengage from the driving device is provided between the tuning gear and the step. A second elastic member is also sleeved outside the limit sleeve, one end of which abuts against the limit plate, and the other end abuts against the tuning gear, which can drive the tuning gear to engage with the driving device. A threaded limit member that limits the limit sleeve on the resonance rod is also installed at the top of the resonance rod.

2. The frequency modulation mechanism according to claim 1, characterized in that: The first elastic member and the second elastic member are springs.

3. The frequency modulation mechanism according to claim 1, characterized in that: The elastic coefficient of the first elastic member is greater than the elastic coefficient of the second elastic member.

4. The frequency modulation mechanism according to claim 1, characterized in that: The resonance rod is provided with a rotation limiting plane, and the rotation limiting plane is used to limit the rotation of the tuning gear relative to the resonance rod.

5. The frequency modulation mechanism according to claim 1, characterized in that: The step is provided with a first limiting groove, and the lower end of the first elastic member is installed in the first limiting groove.

6. The frequency modulation mechanism according to claim 1, characterized in that: The tuning gear is provided with a second limiting groove, and the upper end of the first elastic member is mounted in the second limiting groove.

7. The frequency modulation mechanism according to claim 1, characterized in that: The tuning gear is a worm wheel, and the driving device includes a motor, a worm and a transmission gear. The worm is meshed with the tuning gear, the motor is installed in the cavity, and the transmission gear is connected to the worm and the shaft of the motor.

8. The frequency modulation mechanism according to claim 1, characterized in that: The threaded limiting member includes a screw, and the screw is threadedly connected to the resonance rod to limit the limiting sleeve.

9. The frequency modulation mechanism according to claim 1, characterized in that: The threaded limiting member comprises a nut, a threaded connector is provided on the top of the resonance rod, and the nut is threadedly connected to the threaded connector to limit the limiting sleeve.

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